Boat with adjustable propeller shaft



Oct. 21, 1958 J. G. BAKER BOAT WITH ADJUSTABLE PROPELLER SHAFT 3 Sheets-Sheet 1 Filed July 20, 1955 mm M? 9 fa W W G. M@ 0 Q @N OctfZl, 1958 J. G. BAKER BOAT WITH ADJUSTABLE PROPELLER SHAFT 3 Sheets-Sheet 2 Filed July 20, 1955 @Qhv cord-cm Oct. 21, 1958 J. G. \BAKE'R BOAT WITH ADJUSTABLE PROPELLER SHAFT 3 Sheets-Shet 5 Filed July 20, 1955 l lllllllllllllll IIIIIII ||||l|||| lhlbl lnullll 8 llllllllllllllllllllllllllllllllllllllllll II ask 6 M 1 o 1 w sflm v 0 n a III: F--- 4 BOAT WITH ADJUSTABLE PROPELLER SHAFT I John Gordon Baker, Evansville, Wis.

Application July 20, 1955, Serial No. 523,205

1 Claim. (Cl. 11541) A further object is to provide an adjustable propeller and drive shaft mounting whose bearings are lubricated effectually by the water in which the parts are submerged- A further object is to utilize part of the propeller shaft mounting as a conduit for supplying water to the motor cooling system while the boat is supported above the water surface by the hydrofoils.

The invention also resides in the novel construction of the propeller shaft housing and the manner of adjusting the same.

Other objects and advantages of the invention will be-' come apparent from the following detailed description taken in connection with the accompanying drawings, in which Figure 1 is a fragmentary side elevational view of a motor boat equipped with an inboard propulsion system embodying the novel features of the present invention.

Figs. 2, 3 and 4 are sectional views taken respectively along the lines 22, 33, and4-4 of Fig. 1.

Figs. 5 and 6 are fragmentary sectional views taken respectively along the lines 5-5 and 6-6 of Fig. 4.

Fig. 7 is a sectional view taken along the line 7-7 of Fig. 1.

Fig. 8 is a section taken along the line 88 of Fig. 1.

Fig. 9 is a fragmentary view similar to Fig. 1 showing a modified mounting of the strut supporting the rear end of the propeller shaft, a portion of the strut and its casing being broken away and shown in section.

Fig. 10 is a fragmentary section taken along the line 1010 of Fig. 9.

The improved inboard propulsion system embodying the novel features of the present invention is especially adapted for use on a boat 12 equipped with so-called hydrofoils (not shown) which function by forward motion of the boat to raise and support the latter above the water. Generally stated, an inboard motor 14 with the boat drives a shaft 17 carrying the propeller 13 and mounted to move in the vertical center plane of the boat so as to be disposed close to the bottom as shown in phantom in Fig. 1 during surface operation and in a lower and still submerged position as shown in full when the boat is supported above the water surface by the hydrofoils.

The motor 14 is supported on the hull bottom 11 and its drive shaft 15 connected through a universal coupling 16 (Fig. 7) within a two part housing 16 to thedownwardly inclined shaft 17 which extends through and is journaled in bearings 19 spaced along the interior of a tube 18. A skeg 18 rigid with the lower end of the tube extends downwardly and rearwardly below the propeller to protect the latter against contact with underwater obstructions.

At the upper end, the tube extends through a bellowslike flexiblecollar 22 closing an opening 22 at the end of an inclined groove 23 formed in the bottom of the boat to receive the propeller tube 18 as the latter is raised toward the hull as shown in phantom in Fig. 1 with the propeller disposed adjacent the rudder 27. It will be observed that one end 22 of the flexible collar 22 is attached around the opening in the hull bottom and the other end 22' is similarly attached around the extreme upper end of the tube 18 thus forming an effective seal. With this arrangement, the joint may be located entirely within the boat while permitting vertical swinging of the tube about the joint center as a fulcrum. When the hydrofoils are used, the tube and drive shaft are lowered to the position shown in full in Fig. 1 by swinging the tube about the axis of the joint 16 as a fulcrum. In this position, the propeller will remain submerged to the proper depth after the boat has risen above the water surface and is supported solely by the hydrofoils.

To reduce the resistance offered to the forward motion of the boat, the tube 18 is made of streamlined cross section with the longer dimension disposed in the vertical center plane of the boat. In this instance, the tube is formed in halves of arcuate cross section converging to and secured together at pointed edges 18 disposed above and below the propeller shaft 17. In view of the low inclination of the tube 18, the eifective streamlining is increased substantially in a horizontal plane as shown in Fig. 8.

Means is provided near the rear end of the boat for guiding the propeller against lateral displacement while permitting free movement in an upright arcuate path as the tube 18 is swung toward and awayfrom the boat bottom about the joint 16 as a fulcrum. This means includes a strut 28 preferably hollow and of streamlined horizontal cross section. To facilitate the streamlining and avoid the necessity of lubrication, the strut is preferably secured rigidly to the top of the tube 18 adjacent the propeller. It projects upwardly through a hole 30 in the boat bottom 11 and above the latter is enclosed in an upright housing 34.

In the form shown in Figs. 1 to 6, the flanged upper end of the strut is fastened to a bar 31 disposed between the halves of a two part plunger 32 and pivoted on a pin 33 whose opposite ends are journaled in blocks 33 slidable along horizontal guide slots 33 in the plunger.

The upper end of the bar 31 is guided between the upper ends of the plunger halves as indicated at 31 The two part plunger is slidable in a cylinder formed by the internal wall of the tubular housing 34 whose lower end is clamped to the boat bottom by bolts 35. Thus, the strut is held firmly against lateral displacement relative to the vertical plane including the propeller shaft axis but free to move longitudinally of such plane and the boat to accommodate manufacturing variations in the propeller, strut, and tube assembly and also permit the arcuate movement of this assembly incident to raising and lowering of the propeller.

The plunger 32 may be raised and lowered in various ways as through a rack bar 36 (see Figs. 4 to 6) connected at 37 to the plunger 32 and meshing at its upper end with a pinion 38. The latter is on a shaft 39 journaled on a cover 40 on the upper end of the tube 34 and adapted to be turned by a hand crank 41. Holding of the crank in any desired position is effected by entry of a spring Patented Oct. 21, 1958 holding the shaft againstturning whereby to maintain the selected position of the propellentubelS. Bu't if theskeg. 18 encounters an obstruction 1 in thewater during operation of the boatronth'e hydrofoils, the'friction brake will slip and allow the tube to be swung upwardly toward" the boat bottom thereby permitting the propeller to'pass' over the obstruction. Byretracting a knob 47,'the detent'42 may be withdrawn'fromthe ring 43 afterlwhich the crank 4-1 may be tnrnedfreely to raise and'lower the plunger 32 and therefore the propeller tube to a'desired position.

In the modified Construction shown infFigs. 9and '10, the strut 28 is arranged to be raised and lowered by '3. hydraulic actuator 50. mounted in the upper end 'of the tubular housing 34 which iscurved somewhatto conform to the arcuate path of .the strut. Clearances 51 are also provided between the strut and the housingwalls in the center plane of the boat but opposite ,sides ofthe strut are guided between the side walls 56 of the, housing was shown in Fig. 10 so that, as before, the strut fish-held against lateral displacement as his being swungin its.

arcuate path about the universal joint 16. The..piston rod 52.0f thethydraulic actuator 50" extends downwardly,

within the housing 34 and the strut and is pivotally connected to the latter by a .pin53. By applying. pressure fiuidto one end or the other of the cylinderofi the actuator 50,: the propeller may be moved to and held in either one of the limit positions shown inu-fullgand linr.

phantom in Fig. 1.

As in the-construction first described, an overload =re-- leasedeviceis provided fordisabling theactuators-50 automatically when an obstruction is encounteredlby theskeg 18a while the propeller is in its lowered position.-.

With afluid pressure actuator, suchreleaseh may be effected by providing a valve 57 loaded by an adjustable spring (not shown) and arranged to release pressure fluid from the upper end of the actuator cylinder in response to the build up of an abnormal pressure therein.

Advantage is taken of the tubular character of the propeller shaft mounting to deliver cooling water to the motor 14 in all positions of the propeller. To this end, one of the tubes, in this instance the tube 18, is perforated near its lowered end as indicated at 21 to provide a Water inlet. In the form shown in Figs. 1 to 7, water is conveyed upwardly along the tube 18 whose extreme upper end is equipped with a fitting 25 for attachment to a hose 26 or other conduit leading to the cooling system of the motor 14. To permit of such flow of the water, the supports 20 for the bearings 19 only partially fill the tube 18 as shown in Fig. 2. The water thus flowing past the bearings serves as a lubricant for the latter.

In the form shown in Figs. 9 and 10, the cooling Waterisconducted upwardly through part of--the tube- 18 and the hollow strut 28. For this purpose, a tube suitably mounted within the strut is extended downwardly to a point near the water inlet 21. At its upper end and above the boat bottom, the tube is connected to a flexible hose 56 which extends upwardly and out of the housing 34 near the top of the latter and then to the intake of the motor cooling system.

Withthe' propeller mounting above described, theinboard propulsion system of the boat is adaptable quickly and conveniently for either surface or hydrofoil operation. At'the'same time, the mounting-otters minimum resistance to advance of the boat through the water and provides a supply of cooling Water automatically and Without attention on the part of the boat operator.

This application is a continuation-in-part of my co pending application Serial No. 327,224, filed December 22;"1952 now abandoned."

I claim as my invention The combinationiof, a bdatjan elongated tube'eXtend-- ing down througlr'the bottom'of the boat and downwardly; and rearwardly beneath"the'latter,' a shaftextending through'said'tube and journaled" in the 'latte'r"at"points spaced along "the tube, a propeller carried byjthelower" end of said shaft, means supporting said shaft and said tube at their "upper ends for swingingof the tube and" propeller in a vertical plane toward and away from the bottom of the boat, an inboard engine in said boat uni'-, versally'coupled to said shaft," a strut attachedtothe' lower end portion .of said tube and upstanding through said boatlbottom,'a housing within the boat having. an

internal cylindrical surface enclosing the upper portion of 'said strut, a member guided in and slidable 'alongj said cylindrical surface and providing opposed guide surfaces paralleling' said vertical plane and slidably engag ing opposite sides of said strut to permit up, and down movement thereof within said housing while holding the strut against displacement. laterally of said plane, and

means pivotallyflconnectingsaid strut and said member together for up and down movement in unison and for relative-swiveling about an axis disposed perpendicular to said-plane and spaced below the upper end of said strut.

References Cited in-the file of this patent UNITED STATES PATENTS 

